Note:The Refresh Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information. Consider using it before going through a lengthy troubleshooting process.

Uninstall from Firefox Safe Mode

If you can't access the Add-ons Manager or if the Remove button is grayed out for a certain add-on, you may need to uninstall it from Firefox Safe Mode.

Click the menu button
, click help
Click the menu button
, click Help and select Restart with Add-ons Disabled…. Firefox will start up with the Firefox Safe Mode dialog.

Note: You can also start Firefox in Safe Mode by holding down the shift key while starting Firefox.holding down the option key while starting Firefox.quitting Firefox and then going to your Terminal and running: firefox -safe-modeYou may need to specify the Firefox installation path (e.g. /usr/lib/firefox)

Extensions installed by other software

Sometimes installing or updating other software will add an extension which can't be removed from within the Firefox Add-ons manager because its Remove button is not functional.

The software that added the Firefox extension may include an option to remove it. You should visit the support site of the software provider for more information. As an alternative, simply disable the extension in the Firefox Add-ons manager if you no longer wish to use it. To disable the extension, select it, then click on its Disable button. The extension will be disabled after you restart Firefox.

Microsoft .NET Framework Assistant

If you have programs that use Microsoft .NET Framework components, a Microsoft update may have installed an extension called Microsoft .NET Framework Assistant.

Open the extensions folder inside your profile folder. Inside the extensions folder there are folders or XPI files for each extension and theme you have installed.

To determine which folder or XPI file corresponds to the extension you want to uninstall, return to Firefox and the Troubleshooting Information tab.

In the Extensions section, find the extension you want to remove and note the string in the ID column.

Click the menu button
and then click ExitQuit
.

Click the Firefox menu
, then click Exit.Click the Firefox menu at the top of the screen, then click Quit Firefox.Click the Firefox menu
, then click Quit.

Delete the folder or XPI file that corresponds to the extension ID you noted above.

Globally installed extensions

In rare cases, extensions are installed globally, into the Firefox installation folder. See this Mozilla Developer Network article for more information. Follow these steps to remove a globally installed extension:

Click the menu button
and then click ExitQuit
.

Click the Firefox menu
, then click Exit.Click the Firefox menu at the top of the screen, then click Quit Firefox.Click the Firefox menu
, then click Quit.

Go to your Firefox installation folder.

Go to the browser/extensions folder inside the installation folder.

Follow the steps above to locate the appropriate folder or XPI file to delete.

Click the menu button
and then click ExitQuit
.

Click the Firefox menu
, then click Exit.Click the Firefox menu at the top of the screen, then click Quit Firefox.Click the Firefox menu
, then click Quit.

Go to Library/Application Support/Mozilla/

Open the Extensions/{ec8030f7-c20a-464f-9b0e-13a3a9e97384} folder.

Follow the steps above to locate the appropriate folder or XPI file to delete.

Click the menu button
and then click ExitQuit
.

Click the Firefox menu
, then click Exit.Click the Firefox menu at the top of the screen, then click Quit Firefox.Click the Firefox menu
, then click Quit.

Go to the following folders:

/usr/lib/mozilla/extensions/{ec8030f7-c20a-464f-9b0e-13a3a9e97384}/

/usr/lib64/mozilla/extensions/{ec8030f7-c20a-464f-9b0e-13a3a9e97384}/

/usr/share/mozilla/extensions/{ec8030f7-c20a-464f-9b0e-13a3a9e97384}/

Follow the steps above to locate the appropriate folder or XPI file to delete.